Topic: old stereo mic with 1/4" inputs > warm-mod UA5 > JB3

[kgreener]

I'm hoping someone can help me with this:

I picked up a couple of cheap, old battery-powered stereo mics (that actually don't sound half-bad) off eBay that I'm fooling around with, and would like to try running them through my warm-mod UA5.  Each one of these mics runs on either a AA or C battery, and each one has dual 1/4" phono-type plugs for right/left (see picture for an example)



I realize the 1/4" inputs on my UA5 are disabled due to the w-mod...can I just buy some 1/4" female-to-XLR male adapters?  Or do I need a transformer of some sort?  I'm not even sure if a mic such as this is hi-z or lo-z.  Can this even be done?  If so, will I be able to use the gain knobs on the UA5?

P.S. I'm hoping to use the front panel inputs on the UA5 and not anything on the back, such as the RCA's...my UA5 is setup nicely in a Rakgear pack, velcroed to the rack, and I'm trying to prevent having to take the UA5 out of it's current, semi-permanent position.

Thanks in advance to anyone who can help! 

[hexyjones]

I have a nice collection of Realistic Stereo mics...I'm going to make a web page about them once I complete my collection.

There are 4 models that I am aware of...

I used to have one of those ECM-99s like you have pictured...they are pretty nice...

[kgreener]

Thanks a bunch, Moke, +T fer sure.  I like your 1/4" > XLR suggestion better, as I would like to go thru the front panel of my UA5 vs. the rear.  As far as an unbalanced adapter goes, would something like this work? 

http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&category%5Fname=CTLG%5F011%5F003%5F001%5F007&product%5Fid=274%2D017.

or

http://www.bhphotovideo.com/bnh/controller/home?O=productlist&A=details&Q=&sku=133554&is=REG

I'm still fuzzy on the unbalanced/balanced stuff.  The Radio Shack item mentions transformer, but it's listed as an adapter/transformer, so hopefully this will just act as an adapter?  Not sure if a transformer would screw me up or not.

Again, +T for the quick response

[mirth]

Yeah, definitely go thru the front inputs otherwise you won't be able to apply any gain and won't see as much benefit from the wmod.

[hexyjones]

Balanced vs. Unbalanced really has nothing to do with Phantom Power...

It's more about the length of the cable you can use...you can use much longer cable runs with balanced connections.

[kgreener]

excellent...cable run will be 15' max (more like 12' or less), so i should be good to go.  i'll be stopping at rat shack on the way home to try these adapters, i hope this works!  i'll report back either way...

thanks again, +T's to all

[hexyjones]

And check the impedence of the mic -  if you have the spec sheet...

A lot of those old condeser mics are around 600 ohms...close enough to LowZ for me...

Remember - just cuz it's an unbalanced connection doesn't mean its HighZ...

You may not really need the transformers in those Radio Shack adapters...you wont hurt anything if you use them...but a lot of purists would sneer at that RS transformer...

You may just need straight adapters...

[kgreener]

ya, i was thinking the same thing about the Rats, but i guess i'm just so anxious and want to try it right away, that's why i'm thinking about getting them (for now).  what i might do is try them, if they work, great, i'll just return them to rat shack, get my money back, and then get some Hosa's (I think this is what I want: http://www.hosatech.com/hosa/products/GXJ-235.html). 

some of these mics came with documentation, good idea about checking the specs on them...  +T for all your help

[kgreener]

ha, funny you should mention this, i have an old Marantz PMD-340 stereo cassette recorder that I've tried these mics on.  Sony mics (1/4" inputs) > PMD-340 > rca outs - 1/8" mini > JB3.   Recorded a gig a few weeks ago, it came out decent, BUT...   i was recording a 90 min. cassette at the same time...okay, no worries, right?  Yes worries...tape ended at 45 minutes, which automatically turned off the unit.  I was so into playing (one long 90 min. set) that i totally forgot about the deck turning off.  Doh!  I probably couldn't have got to the machine in the middle of a gig anyway, didn't have any pals to help me out.  I guess the only way to keep it going constantly is to bag the cassette, and keep it in pause mode.  Oh well, 45 minutes is better than nothing i reckon...

A lesson learned the hard way 

[hexyjones]

ya, i was thinking the same thing about the Rats, but i guess i'm just so anxious and want to try it right away, that's why i'm thinking about getting them (for now).  what i might do is try them, if they work, great, i'll just return them to rat shack, get my money back, and then get some Hosa's (I think this is what I want: http://www.hosatech.com/hosa/products/GXJ-235.html). 

some of these mics came with documentation, good idea about checking the specs on them...  +T for all your help

Actually - those AREN'T the ones - the HOSA product is for a 1/4 Balanced...that's TRS...(tip-ring-sleve = 3 conductors just like an XLR) - also known as a stereo phone plug...just a different app.

That said - they might work anyway...I forget what happens when you plug a 1/4 unbalanced into an 1/4 TRS balanced...it may still work...

[kgreener]

yeah, i was wondering the same thing.  hopefully with the shorter cable run it won't make a difference.  i'll first give the rat shack's a go to see if the dang thing works at all!

[hexyjones]

ha, funny you should mention this, i have an old Marantz PMD-340 stereo cassette recorder that I've tried these mics on.  Sony mics (1/4" inputs) > PMD-340 > rca outs - 1/8" mini > JB3.   Recorded a gig a few weeks ago, it came out decent, BUT...   i was recording a 90 min. cassette at the same time...okay, no worries, right?  Yes worries...tape ended at 45 minutes, which automatically turned off the unit.  I was so into playing (one long 90 min. set) that i totally forgot about the deck turning off.  Doh!  I probably couldn't have got to the machine in the middle of a gig anyway, didn't have any pals to help me out.  I guess the only way to keep it going constantly is to bag the cassette, and keep it in pause mode.  Oh well, 45 minutes is better than nothing i reckon...

A lesson learned the hard way 

Hmm...do you mean a Marantz-430? Thats a three head deck...hope you had the monitor set to "Source" -

If you had it set to "Tape" - you were recording the tape playback...(three heads...)

The reason I ask...many - (not all) - 3 head decks will pass signal whether the deck is in record mode, or not...I've not run any of the Marantz decks...so I am talking out my ass at this point...

[kgreener]

no, that (pmd430) is the newer cassette deck (relatively speaking), this is what i have:



not sure if it's as robust as the 430.  i will check the manual to see if it has the source function, but i don't see it readily on this unit.  good to know this in case i pursue a 430 in the future...thanks man.

[hexyjones]

no, that (pmd430) is the newer cassette deck (relatively speaking), this is what i have:

not sure if it's as robust as the 430.  i will check the manual to see if it has the source function, but i don't see it readily on this unit.  good to know this in case i pursue a 430 in the future...thanks man.

Wow - beautiful old school deck...if it's not three head deck...no worries...

On my Sony D5 - I can push down the record button alone...(without the Play button) and it will turn on the decks electronics...but not the motors/trasport...so I can use it as preamp...

[hexyjones]

Hexy,


Very interesting lineage there : AT817 > *SonyTCD5 > RSAD > NJB3

*(as in the D5 cassette deck, right?)

I used my TC-D5M as a preamp, for gain, in my first classical recording attempt. It gave me a nice fat sound!
That Sony stereo mics 1/4" would fit quite nicely into my old d5m!

Yep - using the D5 as a preamp...actually using a Yamaha MG 10/2 mixer now...right into the JB3 analog ins...

The "RSAD" - not really using that...a Realistic A/D converter...it actually worked ok...but I'm paranoid about overloading - no clip light on this 25 dollar A/D...optical out though!!!

[kgreener]

well, picked up a pair of these on the way home http://www.radioshack.com/product.asp?cookie%5Ftest=1&catalog%5Fname=CTLG&category%5Fname=CTLG%5F011%5F003%5F001%5F007&product%5Fid=274%2D017

eh, it works, but not very good in that i can barely get any gain, even with the UA5 cranked to the max.  i can hear what i'm recording, but it's a weak signal, it should be more robust.  do I have the wrong part?  good chance of that, especially since these are listed as transformers.  do transformers lower the signal?  damn i'm clueless about some of this stuff.

i'm pretty sure this is gonna work, i guess i just need the correct adapters.  guess i'll look up the Hosa's as mentioned earlier.  any more help would be appreciated!

[kgreener]

I should also mention, when i tried this last night, i noticed it didn't matter whether the UA5 phantom power button was on or not...the volume pots worked whether it was on or off (albeit with not much gain, as previously mentioned).  does this tell anyone anything?  Do you think it's my connectors?   FWIW, i ordered these late last night, i hope they do the trick:

http://www.audiogear.com/cgi-bin/shopper.cgi?key=AdptMx-Qmf&preadd=action

[hexyjones]

I should also mention, when i tried this last night, i noticed it didn't matter whether the UA5 phantom power button was on or not...the volume pots worked whether it was on or off (albeit with not much gain, as previously mentioned).  does this tell anyone anything?  Do you think it's my connectors?   FWIW, i ordered these late last night, i hope they do the trick:

http://www.audiogear.com/cgi-bin/shopper.cgi?key=AdptMx-Qmf&preadd=action

Phanton is irrelevant for your application...on or off will make no difference...

[kgreener]

why is that?  i have run these mics using a battery box, and can increase or decrease the gain effectively on the battery box.  is it the 9V vs. 48v phantom that's in question here?  i wonder why i can get a teeny bit of control using the UA5 knobs when it's in the maxed out position?  hmm...

[hexyjones]

I should also mention, when i tried this last night, i noticed it didn't matter whether the UA5 phantom power button was on or not...the volume pots worked whether it was on or off (albeit with not much gain, as previously mentioned).  does this tell anyone anything?  Do you think it's my connectors?   FWIW, i ordered these late last night, i hope they do the trick:

http://www.audiogear.com/cgi-bin/shopper.cgi?key=AdptMx-Qmf&preadd=action

Those are just what you want....

Question...Did your levels seem a bit low when using the Marantz?

It is likely that the transformer is eating up some of your signal...but also consider the following...

"Back Electret" condenser mics...It is my understanding that these capsules will only keep their "back electret" charge for about 20 years...

Once the charge begins to fade...the output will diminish...

Check your spec sheet...For some reason I want to say that ECM 99 is a "capacitor" mic...?

I cant remember if condenser and capicitor mean the same thing...

[hexyjones]

why is that?  i have run these mics using a battery box, and can increase or decrease the gain effectively on the battery box.  is it the 9V vs. 48v phantom that's in question here?  i wonder why i can get a teeny bit of control using the UA5 knobs when it's in the maxed out position?  hmm...

I get a little foggy on these battery box things...I am under the impression they are for the mini-disc crowd...for use with "Plug In Power" mics...
or to be used with the Line Level inputs on MD/DAT decks...not sure of what use they would be in this application.

I am also unfamiliar with the seemingly famous UA5...assuming you are using a XLR mic level input...(not Line Level)

[hexyjones]

. And, remember, that there is no way that you can achieve live room spl's in home testing!

Good point Moke...unless you have an electric guitar and amp handy...your home stereo wont create that kind of SPL...

[kgreener]

thanks guys.  batteries are fresh (i use plural as i was trying three single-point mics, a sony, a jvc, and a realistic, which, btw, has better response IMO than the sony and jvc...go figure), and i believe all are low impedance, self-powered (damn, forgot to look at the documentation last night, sorry).  the jvc and realistic have an on/off switch on them, the sony does not. 

i bought the battery box when i first started taping, and pulled some decent shows going mics > batt box > MD, then mics > batt box > JB3 (line-in) after i ditched the MD.  my testing scenario is...my car!  (i have to do this otherwise i would wake my two kids up)   It's a kick-ass car stereo system, gets very loud, and i've used it before to test stuff.  Past tests with mics > batt box > JB3 have created very lively response, with levels maxing out just where i want them (link below will show you the batt box i'm using, it's pretty cool actually, but i don't trust all of the 1/8" connectors in the field as much as i would the UA5):

http://www.reactivesounds.com/spa2.php

thanks again guys.  hey, i don't want to waste any more of your time, i've probably asked too many questions already, and i don't want to overstay my welcome.  i was just hoping to use one of these single-points in a quick & dirty situation, like band practices, or in a dive bar, ie times when i don't feel like setting up my Josephson's.  Was just hoping to run this thru the UA5, get some gain from it, as well as optical out into the JB3.  Thanks again!

[kgreener]

i'm all set!  these adapters did the trick, just as hexyjones and moke said they would, thanks guys:

http://www.audiogear.com/cgi-bin/shopper.cgi?key=AdptMx-Qmf&preadd=action

you're right, i don't need to turn on phantom, all that does is distort things, it runs way too hot.  i'm get plenty of gain from the front knobs, and my in-car audio testing sounds just like it should.  those rat shack transformers were "choking" the mic, glad to be rid of them.

hard to believe an inexpensive single-point mic can sound so good thru a w-mod...can't wait to get out and try it on some real live music.  thanks again guys, and +T's all around.

peace,
Keith

[dklein]

by the way, your 'battery box' is actually a preamp - there's a big difference!

[kgreener]

"by the way, your 'battery box' is actually a preamp - there's a big difference!"

Dave, what do you mean by this statement?  Do you mean that my "battery box" is actually a decent piece of equipment, or a piece of sh**?       Or were you just pointing out that it does more than provide battery power?

I just woke up, maybe I'll read this again later when I've woken up!

Thanks Dave, +T

[Brian Skalinder]

Dave, what do you mean by this statement?  Do you mean that my "battery box" is actually a decent piece of equipment, or a piece of sh**?       Or were you just pointing out that it does more than provide battery power?

Battery boxes provide power to the mics, nothing more.  Preamps provide phantom power and gain, and in your case the UA-5 also acts as an ADC.  The power provided by battery box or preamp is different, too.  Battery boxes typically provide lower voltage, usually around 9v.  Preamps with phantom power usually provide 48v phantom power.

I'm not positive on this last part: the way the power is provided is different, too - phantom v. whatever you call battery box power.  Battery boxes pass power through a (+) and (-)  cable (two wires), while phantom is passed using (+), (-), and ground (3 wires).  I think.  Someone else can probably explain this part of it better than I can - I feel like I used to know the difference, but can't pull it outta my noggin now.

And your wmod-UA5 is a great piece of gear!  Definitely not a POS.

[kgreener]

Thanks for the info Brian, I appreciate it!  +T